Switching arrangement

ABSTRACT

A switching arrangement for use in programming systems or the like wherein the hollow hub of a rotary selector accommodates a stack of coaxial ring-shaped cams whose lobes can pivot two-armed armatures mounted on the pole shoes of a fixed permanent magnet. The pole shoes carry semiconductors whose electrical resistance varies as a function of the intensity of the magnet field, and such intensity is changed in response to pivoting of armatures on rotation of the selector to predetermined angular positions. The semiconductors are connected in logical circuits.

United States Patent H; 340/365, 357, 364; 307/309; 323/94 H; 200/11 TW; 335/2; 3 10/2 I 22, 32, 33, DIG. 4

[56] References Cited UNITED STATES PATENTS 3,471,722 10/1969 Hini 338/32X 3,248,700 4/1966 Sinn 340/357 X Primary Examiner-Rodney D. Bennett, .Ir. Assistant Examiner--R. Kinberg Attorney-Michael S. Striker ABSTRACT: A switching arrangement for use in programming systems or the like wherein the hollow hub of a rotary selector accommodates a stack of coaxial ring-shaped cams whose lobes can pivot two-armed armatures mounted on the pole shoes of a fixed permanent magnet. The pole shoes carry semiconductors whose electrical resistance varies as a function of the intensity of the magnet field, and such intensity is changed in response to pivoting of armatures on rotation of the selector to predetermined angular positions. The semiconductors are connected in logical circuits.

PATENTED DEC 7191:

Fig. I

5 25d 250% F 26a 27 Inventor.-

Rudolf Hubrich by //r'( 914/ his Attorney SWITCHING ARRANGEMENT BACKGROUND OF THE INVENTION The present invention relates to switching arrangements in general, and more particularly to arrangements which can regulate the sequence of operations performed by a programming system, control system, computer, or the like. Still more particularly, the invention relates to arrangements which can trigger the generation of a Substantial number of electric signals and which can effect generation of such signals in any desired sequence or combination.

Presently known switching arrangements comprise customary electric switches wherein a moving (sliding) contact is caused to engage with or to be disengaged from a fixed contact. A drawback of such constructions is that the contacts are subjected to considerable wear and that the switches are highly sensitive to external influences such as vibration and/or moisture. This is particularly undesirable when the switching arrangement is utilized in a computer or an analogous automatic system.

SUMMARY OF THE INVENTION An object of the invention is to provide a switching arrangement wherein the wear on movable and fixed parts is negligible, which is more reliable than presently known switching arrangements, which can be subjected to rough treatment without influencing its operation or reliability, and which can initiate the generation of electric signals in any desired sequence or combination.

The improved switching arrangement comprises a housing, ring-shaped cam means rotatable in the housing about a fixed axis, preferably by means of a disk-shaped selector which is accessible at the exterior of the housing and has a hollow cylindrical hub for the cam means, preferably block-shaped permanent magnet means fixedly mounted in the housing and spacedly surrounded by the cam means, a plurality of magnetizable armatures mounted in the housing in the field of the magnet means and movable between first and second positions to thereby redirect the magnetic field, the armatures normally assuming one of their positions under the action of the magnet means and being moved to other positions by the cam means in predetermined angular positions of the selector, and a plurality of semiconductors whose resistance to the flow of electric current varies as a function of changes in the magnetic field. Each semiconductor is associated with one of the armatures so that its resistance changes in response to movement of the associated annature. The semiconductors are connected in logical circuits to initiate the generation of electric signals in response to movement of associated armatures between first and second positions.

The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The improved switching arrangement itself, however, both as to its construction and its mode of operation, together with additional features and advantages thereof, will be best understood upon perusal of the following detailed description of certain specific embodiments with reference to the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is an enlarged side elevational view of a switching arrangement which embodies the invention, with the cover of the housing omitted;

FIG. 2 is an end elevational view of the switching arrangement as seen from the left-hand side of FIG. I, and further showing two additional switching arrangements which form therewith a stack;

FIG. 3 is an axial sectional view of the rotary selector as seen in the direction of arrows from the line A-A of FIG. 1;

FIG. 4 is an axial sectional view of the permanent magnet means as seen in the direction of arrows from the line A-A of FIG. 1; and

FIG. 5 is a circuit diagram of electrical circuitry embodying the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The switching arrangement which is shown in the drawing comprises a housing I consisting of synthetic plastic material and accommodating a rotary disk-shaped selector 2 here shown as a star wheel. At least one prong of the selector 2 extends through an opening or window Ia of the housing I so that it can be engaged by a finger to facilitate its rotation. The selector includes a hollow cylindrical hub 3 (see particularly FIG. 3) whose internal surface is formed with radially outwardly extending axially parallel grooves 4 for reception of external projections provided on a stack of ring-shaped cams 5. These cams can be inserted or withdrawn in axial direction of the hub 3 and each thereof is formed with internal projections or lobes 6 whose distribution about the axis of the hub 3 determines the sequence of switching operations which are performed in response to rotation of the selector 2 and/or in response to setting the selector in a given angular position.

The interior of the housing 1 further accommodates a casing or holder 7 which extends into the interior of the hub 3 (i.e., into the area surrounded by the cams 5) and supports a block-shaped pennanent magnet 8. The latter is flanked by two strip-shaped pole shoes 9 which are located opposite each other and are secured to the casing 7 so that they establish a connection between the casing and the permanent magnet 8. At least one end portion of each pole shoe 9 extends beyond the magnet 8. The end portions 10 of the pole shoes 9 serve as fulcra or knife edge bearings for two armatures 11 each of which is a two-armed lever having portions or arms 12 and 13. Each armature 11 preferably consists of a single bent strip of ferromagnetic material and its arm 12 serves mainly to guide the magnetic flux. The arms 13 serve as a motion transmitting means, i.e., to etfect angular movements of respective armatures 11 between two end positions. The arms 13 can receive motion from radially movable roller-shaped actuating members 14 which constitute followers and track the internal surfaces of the adjoining cams 5. The followers 14 are mounted in the casing 7 and are movable radially inwardly by the lobes 6 of the associated cams 5. The planes of these followers are parallel to the planes of upper and lower side faces of the mag: net 8. When the operator rotates the selector 2 to thereby rotate the cams 5, the lobes 6 cause certain followers 14 to move inwardly and to thereby pivot the corresponding armatures II from one to the other end position. These armatures automatically reassume the end positions corresponding to that of the lower armature 11 shown in FIG. I because their arms 12 are attracted by the magnet 8. The distribution of lobes 6 on the cams S detennines those angular positions of the selector 2 in which selected armatures I] assume their first or second end positions. The upper armature of FIG. 1 is shown in a position in which its arm 12 is removed from the pennanent magnet 8 because the other arm 13 is engaged by the adjoining follower 14.

The other end portions of pole shoes 9 support semiconductors 15 of the type which act as resistors and whose resistance is influenced by the magnetic flux. Such flux changes when an arm 12 moves with reference to the magnet 8, Le, with reference to the adjoining pole shoe 9. This changes the width of the air gap between the semiconductor l5 and the adjacent arm 12. The ohmic resistance of a semiconductor 15 changes when the arm 12 is pivoted toward or away from the magnet 8; such change in ohmic resistance can be utilized to generate or to initiate generation of a signal which is transmitted to a logical element in circuit with the corresponding semiconductor. FIG. 4 indicates by phantom lines a platelike conductor 16 which can connect the semiconductors 15 with the corresponding logical circuit. Such logical circuits (not specifically shown) are preferably installed in the housing I.

The outer sides of the pole shoes 9 are coated with liners or layers 17 of the insulating material which serve to secure the pole shoes (and hence the magnet 8) to the holder 7. Each such liner 17 also insures that the corresponding armature 11 cannot stick in one of its end positions.

The mounting and configuration of pole shoes 9 and armatures 11 are preferably such that the magnetic field is diverted when the arm 12 moves away from the magnet 8. The magnetic flux through each semiconductor 15 in one position of the corresponding armature should be a multiple (at least double but preferably at least quintuple) of the magnetic flux in other position of the armature.

When a lobe 6 engages the corresponding follower 14, the follower moves radially inwardly and pivots the associated armature 11 about the fulcrum 10. The follower 14 returns to its radially outermost position, i.e., into the path of movement of lobes 6 on the corresponding cam 5, when a lobe 6 moves away from its outer side because the magnet 8 immediately attracts the corresponding arm 12 so that the arm 13 pushes the follower toward the internal surface of the adjoining cam 5.

Each cam can be readily removed from the hub 3 and replaced with a differently configurated cam. Furthermore, the sequence in which the cams 5 are inserted can be changed at will so that the programmer can readily select a desired sequence and/or combination of signals.

An advantage of the switching arrangement which is shown in FIGS. 1 to 4 is that it does not necessitate the use of springs which would bias the armatures 11 to one of their end positions. Each armature 11 is permanently urged to one of its end positions (see the lower armature ll of FIG. 1) by the magnet 8. This magnet also attracts the armature 11 which assumes the other end position (shown in the upper part of FIG. 1); it preferably consists of a material which is known as Alnico 500 (trademark) and is readily available on the market. For example, the magnet 8 can attract the arm 12 of an armature 11 with 30 pond when the other arm is depressed by the adjacent follower 14, and the same arm 12 is attracted with 80 pond when the follower l4 permits the corresponding arm 13 to move away from the adjacent pole shoe 9. Thus, the force with which the magnet 8 attracts the arm 12 of the lower armature 11 of FIG. 1 is a multiple of the force with which the magnet 8 attracts the arm 12 of the upper armature 11. This is advantageous when the switching arrangement is installed in an apparatus which is likely to be subjected to rough treatment. Thus, the armature 11 whose arm 12 is attracted by the magnet 8 while the other arm 13 is not depressed by the follower 14 will remain in desired position when the corresponding semiconductor 15 is in circuit with the transistor or transistors of the associated logical element. The same holds true when a follower 14 causes the adjacent armature 11 to assume the end position corresponding to that shown for the upper armature of FIG. 11. The force with which the magnet 8 attracts the arm 12 ensures that the arm 13 bears against the follower 14. If the logical circuit is an electronic circuit, it preferably constitutes an integrated element.

FIG. 3 shows that the switching arrangement comprises four concentric cams 5 which form a stack in the interior of the hub 3. Consequently, the arrangement comprises four followers 14, one for each of the cams 5, four armatures 11 and four semiconductors 15. Such arrangement permits for selection of a substantial number of combinations. The aforementioned platelike conductor 16 which is connected with the semiconductors 15 also serves as a cover or lid for the housing 1. The holder 7 is provided with two studs 18 which extend into bores provided in the conductor 16.

Several switching arrangements can be grouped together and the hubs 3 of the selectors 2 can be provided with symbols or other indicia to point out the momentary positions of the disks. FIG. 2 shows a set of three adjoining housings 1 assembled in such a way that a window lb in one end face of each housing exposes a numeral (see the numeral 7 in the median window 1b) which is indicative of the momentary setting of the respective selector.

The distribution of cams 6 in each housing 1 is such that a given angular position of the disk 2 corresponds to a given resistance of each semiconductor 15. The cams can be distributed in such a way that the selector 2 must be rotated through identical angles to move from a preceding position to the next-following position or vice versa. Otherwise stated, a given combination of signals is produced by moving the selector 2 from a starting or zero position through a predetermined angle until the disk reaches a predetermined angular position. Each housing 1 accommodates at least two armatures 11, depending on the number of cams 5.

FIG. 5 illustrates diagrammatically the circuitry associated with the switching arrangement as described above. Each of the four semiconductors 15a, 15b, 15c, 15d is connected in series with a resistance 25a, 25b, 25c, 25d of 3,300 ohm so that four separate voltage dividers are obtained each of them being connected to the bases of one of the transistors (type I N 914) 26a, 26b, 26c, 26d.

When arm 12 (see FIG. 1) is pivoted and therefore the way of the magnetic flux is shifted, the ohmic resistance changes from 40 ohm to about 200 ohm, the potential at the base of the associated transistor changes accordingly and a signal is derived at one of the outputs 27, 28, 29, 30 respectively. Terminal 31 is connected by means of four diodes 32 to the bases of the transistors and by applying a blocking potential to said terminal these transistors can be blocked. This can be useful if the switching arrangement is connected with a computer.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features which fairly constitute essential characteristics of the generic and specific aspects of my contribution to the art.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims:

1. A switching arrangement, particularly for use in programming and analogous apparatus, comprising a housing; ringshaped cam means rotatable in said housing about a fixed axis to and from a zero position; permanent magnet means spacedly surrounded by said cam means; a plurality of magnetizable armatures mounted in the housing in the field of said magnet means and movable between first and second positions to thereby redirect said field, said armatures normally assuming said first positions under the action of said magnet means and being moved to second positions by said cam means in predetermined angular positions of said cam means; and a plurality of semiconductors whose resistance to the flow of electric current varies as a function of the intensity of magnetic field, each of said semiconductors being associated with one of said armatures so that the resistance of said semiconductors changes in response to movement of associated armatures.

2. A switching arrangement as defined in claim 1, further comprising electric circuit means including conductor means connected with said semiconductors.

3. A switching arrangement as defined in claim 1, further comprising selector means for rotating said cam means, said selector means having a hollow portion and said cam means being accommodated in said hollow portion, said cam means having lobes provided on the internal surfaces thereof and operative to effect movement of said armatures in response to rotation of said cam means by said selector means.

4. A switching arrangement as defined in claim 1, wherein the number of magnetic flux lines passing through said semiconductors in one position of the respective armatures is a multiple of the number of flux lines passing through the semiconductors in the other positions of the respective armatures.

5. A switching arrangement as defined in claim 1, further comprising a pair of pole shoes flanking said magnet means from opposite sides, said semiconductors being mounted on said pole shoes and said pole shoes defining fulcra for said armatures.

6. A switching arrangement as defined in claim 5, wherein said pole shoes have projecting portions extending beyond said magnet means and wherein said semiconductors are supported by said projecting portions.

7. A switching arrangement as defined in claim 5, wherein each of said armatures comprises a first portion which receives motion from said cam means and a second portion which redirects the magnetic field in response to movement of said first portion.

8. A switching arrangement as defined in claim 1, wherein said armatures are arranged to redirect the magnetic field of said magnet means in response to movement between said first and second positions thereof.

9. A switching arrangement as defined in claim 1, wherein the magnetic flux through each of said semiconductors in one position of the respective armature is at least five times the flux in the other position of the respective armature.

l0. A switching arrangement as defined in claim I, further comprising selector means for rotating said cam means, said selector means comprising a hollow portion and said cam means comprising a plurality of discrete ring-shaped cams coaxially mounted in said hollow portion and having inwardly extending lobes.

11. A switching arrangement as defined in claim 1, further comprising holder means fixedly mounted in said housing and supporting said magnet means, and a plurality of follower means movably mounted in said holder means for transmitting motion from said cam means to said armatures.

12. A switching arrangement as defined in claim 11, wherein said cam means comprises inwardly extending lobes and wherein each of said follower means extends into the path of movement of said lobes in one position of the corresponding armature and moves the corresponding armature to other position in response to engagement with a lobe.

13. A switching arrangement as defined in claim 1, further comprising substantially roller-shaped follower means movable radially of said axis and operative to transmit motion from said cam means to said armatures.

14. A switching arrangement as defined in claim I, further comprising hollow disk-shaped selector means for rotating said cam means, said cam means comprising a plurality of discrete coaxial ring cams mounted in said selector means.

15. A switching arrangement as defined in claim 15, wherein said selector means is provided with. means for indicating the angular positions of said cam means.

16. A switching arrangement as defined in claim 14, wherein said selector means comprises a cylindrical hub and wherein said cams are removably and interchangeably accommodated in said hub.

17. A switching arrangement as defined in claim 1, wherein each of said armatures comprises a single strip of ferromagnetic material and constitutes a two-armed lever which is pivotable between said first and second positions, said arrangement further comprising a plurality of pole shoes of ferromagnetic material, said pole shoes flanking said magnet means and defining fulcra for said armatures, each of said semiconductors being mounted on one of said pole shoes and each of said armatures having an arm which is adjacent to the semiconductor on the pole shoe on which the fulcrum for the other armature is provided.

18. A switching arrangement as defined in claim 1, wherein said permanent magnet means comprises a block having two at least substantially parallel end faces, said armatures having each one arm adjacent to the respective end face of said magnet means, and the arrangement further comprising a pole shoe fixed to each of said faces of said magnet means and follower means cooperating with said cam means to transmit motion to said arms of said armatures in response to rotation of said cam means, said follower means being movable substantially in a plane of symmetry extending through said block between said end faces thereof. 

1. A switching arrangement, particularly for use in programming and analogous apparatus, comprising a housing; ring-shaped cam means rotatable in said housing about a fixed axis to and from a zero position; permanent magnet means spacedly surrounded by said cam means; a plurality of magnetizable armatures mounted in the housing in the field of said magnet means and movable between first and second positions to thereby redirect said field, said armatures normally assuming said first positions under the action of said magnet means and being moved to second positions by saiD cam means in predetermined angular positions of said cam means; and a plurality of semiconductors whose resistance to the flow of electric current varies as a function of the intensity of magnetic field, each of said semiconductors being associated with one of said armatures so that the resistance of said semiconductors changes in response to movement of associated armatures.
 2. A switching arrangement as defined in claim 1, further comprising electric circuit means including conductor means connected with said semiconductors.
 3. A switching arrangement as defined in claim 1, further comprising selector means for rotating said cam means, said selector means having a hollow portion and said cam means being accommodated in said hollow portion, said cam means having lobes provided on the internal surfaces thereof and operative to effect movement of said armatures in response to rotation of said cam means by said selector means.
 4. A switching arrangement as defined in claim 1, wherein the number of magnetic flux lines passing through said semiconductors in one position of the respective armatures is a multiple of the number of flux lines passing through the semiconductors in the other positions of the respective armatures.
 5. A switching arrangement as defined in claim 1, further comprising a pair of pole shoes flanking said magnet means from opposite sides, said semiconductors being mounted on said pole shoes and said pole shoes defining fulcra for said armatures.
 6. A switching arrangement as defined in claim 5, wherein said pole shoes have projecting portions extending beyond said magnet means and wherein said semiconductors are supported by said projecting portions.
 7. A switching arrangement as defined in claim 5, wherein each of said armatures comprises a first portion which receives motion from said cam means and a second portion which redirects the magnetic field in response to movement of said first portion.
 8. A switching arrangement as defined in claim 1, wherein said armatures are arranged to redirect the magnetic field of said magnet means in response to movement between said first and second positions thereof.
 9. A switching arrangement as defined in claim 1, wherein the magnetic flux through each of said semiconductors in one position of the respective armature is at least five times the flux in the other position of the respective armature.
 10. A switching arrangement as defined in claim 1, further comprising selector means for rotating said cam means, said selector means comprising a hollow portion and said cam means comprising a plurality of discrete ring-shaped cams coaxially mounted in said hollow portion and having inwardly extending lobes.
 11. A switching arrangement as defined in claim 1, further comprising holder means fixedly mounted in said housing and supporting said magnet means, and a plurality of follower means movably mounted in said holder means for transmitting motion from said cam means to said armatures.
 12. A switching arrangement as defined in claim 11, wherein said cam means comprises inwardly extending lobes and wherein each of said follower means extends into the path of movement of said lobes in one position of the corresponding armature and moves the corresponding armature to other position in response to engagement with a lobe.
 13. A switching arrangement as defined in claim 1, further comprising substantially roller-shaped follower means movable radially of said axis and operative to transmit motion from said cam means to said armatures.
 14. A switching arrangement as defined in claim 1, further comprising hollow disk-shaped selector means for rotating said cam means, said cam means comprising a plurality of discrete coaxial ring cams mounted in said selector means.
 15. A switching arrangement as defined in claim 15, wherein said selector means is provided with means for indicating the angular positions of said cam means.
 16. A switching arrangement as dEfined in claim 14, wherein said selector means comprises a cylindrical hub and wherein said cams are removably and interchangeably accommodated in said hub.
 17. A switching arrangement as defined in claim 1, wherein each of said armatures comprises a single strip of ferromagnetic material and constitutes a two-armed lever which is pivotable between said first and second positions, said arrangement further comprising a plurality of pole shoes of ferromagnetic material, said pole shoes flanking said magnet means and defining fulcra for said armatures, each of said semiconductors being mounted on one of said pole shoes and each of said armatures having an arm which is adjacent to the semiconductor on the pole shoe on which the fulcrum for the other armature is provided.
 18. A switching arrangement as defined in claim 1, wherein said permanent magnet means comprises a block having two at least substantially parallel end faces, said armatures having each one arm adjacent to the respective end face of said magnet means, and the arrangement further comprising a pole shoe fixed to each of said faces of said magnet means and follower means cooperating with said cam means to transmit motion to said arms of said armatures in response to rotation of said cam means, said follower means being movable substantially in a plane of symmetry extending through said block between said end faces thereof. 